1. Field of the Invention
The present invention relates to a rearview mirror assembly for use on an automobile, and more particularly to a support structure for a mirror holder of an automobile rearview mirror assembly.
2. Description of the Prior Art
Rearview mirror assemblies such as those for use on automobiles or the like include remotely controlled motor-driven rearview mirror assemblies. The remotely controlled motor-driven rearview mirror assemblies have a mirror disposed in a mirror housing and horizontally tiltable to give the automobile driver a clear rearward view of following automobiles and other objects.
Usually, the mirror is supported on a face side of a mirror holder made of a resilient synthetic resin such as polypropylene, the mirror holder having a spherical pivot on its back side. The spherical pivot is fitted in a spherical cavity defined in the mirror housing so that the mirror holder is pivotally supported in the mirror housing.
One conventional mirror holder support structure is disclosed in Japanese utility model publication No. 62-25955 published Jul. 2, 1987.
The disclosed conventional mirror holder support structure is used to support the mirror holder of a remotely controlled motor-driven rearview mirror assembly. A mirror is supported on the face side of a mirror holder which has a spherical pivot. The spherical pivot is movably fitted in a spherical cavity defined in a mirror housing. Therefore, the mirror holder is tiltably supported in the mirror housing through the spherical pivot received in the spherical cavity.
The wall surrounding the spherical cavity has a plurality of spaced recesses defined therein, providing a plurality of resilient arms alternating with the recesses. When the mirror holder is assembled into the mirror housing, the spherical pivot can easily be fitted into the spherical cavity because the arms can resiliently be flexed radially outwardly by the spherical pivot as it is forced into the spherical cavity. However, after the spherical pivot has been fitted into the spherical cavity, the spherical pivot may not stably be held in position as the arms are resilient. To keep the spherical pivot stably in the spherical cavity, the conventional mirror holder support structure has a ring spring looped around the arms to tighten the arms on the spherical pivot, thus securely holding the spherical pivot in the spherical cavity.
The conventional mirror holder support structure is however relatively complex and made up of a relatively large number of parts because of the ring spring.